1. Field of the Invention
The present invention relates to a flat panel display, and particularly to a flat panel display having non-evaporable getter material.
2. Discussion of the Related Art
Flat panel displays are packaged vacuum microelectronic devices that are used in connection with computers, television sets, camcorder viewfinders, and other electronic devices. Flat panel displays generally have a rear plate and a front plate facing one another across a narrow vacuum gap. In large flat panel displays, a number of spacers are positioned between the rear plate and the front plate to prevent atmospheric pressure from collapsing the plates together. The rear plate typically has a base substrate upon which a number of sharp, cone-shaped emitters are formed, an insulator layer positioned on the substrate having apertures through which the emitters extend, and an extraction grid formed on the insulator layer around the apertures.
One problem with flat panel displays is that the internal components continuously outgas, which causes the performance of flat panel displays to degrade over time. The effects of outgassing are minimized by placing a special material to absorb the gas (commonly called getter material) within the sealed vacuum space. Accordingly, in order to absorb the gas in the vacuum chamber over a flat panel display's lifetime, a sufficient amount of getter material must be incorporated into the flat panel display before it is sealed.
The getter material generally includes two types: evaporable, and non-evaporable. The former is not suitable for use in flat panel displays because of the possible short-circuit caused by evaporating metal film. When non-evaporable getter materials are used, they are usually arranged in a corner of the flat panel device, but the conductance from the outgassing site to these getters are limited by the narrow space between the flat plates, causing reduction of the getters' absorption efficiency and in consequence the display's performance and lifetime. There are also according solutions in which a separate space for containing getter materials is added to the device, but the structure thereof becomes complicated and the manufacture cost will be increased.
What is needed, therefore is to provide a flat panel display having non-evaporable getter material that has a high absorption efficiency.